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Long before the modern marvels of decongestants and steroids, people understood the simple premise that fortifying the body meant cleansing the body. Neti pots, the squat, teapot-like devices used to flush out one’s sinuses, are the world’s oldest form of nasal irrigation and have been a part of the Indian Ayurvedic yoga tradition for thousands of years. Still, the homeopathic remedy is not impervious to the wisdom of medical science. Here are three common dangers of using a neti pot that, while clear and present, are equally avoidable.

Danger #1: Using The Wrong Water

In 2011, two unrelated deaths occurred in Louisiana, one of a 20-year-old man and the other of a 51-year-old woman, which were believed to have resulted from both using tap water contaminated with the extremely lethal bacteria, Naegleria fowleri.

Best practice dictates you fill your neti pot with distilled or sterile water, which can come from an unopened bottle of water or water you’ve personally run through a home filter with a pore size of less than one micron. Alternatively, you may boil ordinary tap water for three to five minutes and let it cool until it’s lukewarm, before pouring in your neti pot.

A consumer notice released by the U.S. Food and Drug Administration (FDA) last year urges neti pot manufacturers to provide more information to the consumers directly on the products’ packaging. Often, warnings against using basic tap water are left off neti pot labels.

“Some tap water contains low levels of organisms, such as bacteria and protozoa, including amoebas, which may be safe to swallow because stomach acid kills them,” the release states. “But these ‘bugs’ can stay alive in nasal passages and cause potentially serious infections.”

Generally, neti pots will come with their own pre-portioned saline solution packets. But for those making a saline solution on their own, health officials recommend adding one-quarter teaspoon of non-iodized salt for every 8 ounces of water. For coarsely ground salt, add one-half teaspoon.

Danger #2: Improper Cleaning

A good rule of thumb when using a neti pot is to treat it just like you would your dishes. Regular cleaning, meaning after each use, prevents the growth of bacteria on the spout or around the edges of the pot. Pay close attention to the point where the spout connects to the pot, as salt tends to accumulate there more often.

If you are considering buying a neti pot, check to make sure it is dishwasher-safe, and preferably has a wide opening so as to allow thorough flushing of any residual germs.

In the same vein, health officials advise against sharing neti pots, in the same way you wouldn’t share your toothbrush. Because the device’s spout must form a seal on the inner part of your nostril, the bacteria inside your nose can get left behind on the spout’s edge. Sharing a neti pot, even with proper cleaning, increases a person’s risk for transferring this bacteria to someone else.

Danger #3: Overuse

While nasal irrigation with salt water is recommended by roughly 87 percent of physicians, as it can offer short-term symptomatic relief and may improve nasal mucociliary clearance (i.e. you won’t feel stuffed up), there’s a wealth of evidence that suggests prolonged neti pot use may end up hurting you.

One recent study, presented at the annual meeting of the American College of Allergy, Asthma and Immunology in Nov. 2009, found that long-term neti pot users saw an average of eight episodes of recurrent rhinosinusitis per year. That was compared to people who discontinued use and saw an average of three episodes per year. The researchers concluded prolonged exposure to saline solution in the nose depleted the protective blanket of mucous that helps fight infection.

"I don't have anything against nasal saline. But I have something against nasal saline being used long-term on a daily basis," said Dr. Talal Nsouli, the study’s leader. "People who are using nasal saline on a regular basis, it makes them feel like it is helping them, but they are only patching the problem."

Nsouli advises people not to use a neti pot for more than one to three weeks at a time. If people feel congested after that period, Nsouli recommends they see a doctor, as a more serious condition could be underlying their symptoms.